Microwave ovens commonly are used as a convenient means of heating food items. However, when larger food items are heated in a microwave oven, some portions of the food may tend to reach the desired final heating temperature too early in the heating cycle and become dry or charred, while other portions remain underheated or even cold. Thus, there is a need for a package, container, or other construct that controls the rate of heating of the food item so that the food item is suitably and substantially uniformly heated at the end of the heating cycle.